1. Field of the Invention
This invention relates to new antitumor fermentation products and to their reproduction and recovery.
2. Description of the Prior Art
Japanese Kokai No. 55/118499 discloses an antibiotic designated as ATS-1287 which is produced by fermentation of Streptomyces sp. No. 1287. While the properties of ATS-1287 do not appear to correlate with those of either the jildamycin or mantuamycin components of the present invention, a recent publication in J. Antibiotics 36 (6): 639-650 (1983) suggests that ATS-1287 may be a mixture containing jildamycin and mantuamycin. The J. Antibiotics reference discloses compounds ATS-1287A and B (called leptomycin A and B) which are believed to be identical to the jildamycin and mantuamycin compounds of the present invention. The leptomycins, however, are not described as having antitumor activity and the producing microorganism, i.e. Streptomyces sp. No. 1287, can be distinguished from the Streptomyces aburaviensis microorganism used to produce jildamycin and mantuamycin.